Analysis on Alexa ranking mechanism and its influencing factors

Intermediary transaction SEO diagnosis Taobao guest Cloud host technology Hall

A) Alexa Browse rate statistics and ranking prerequisites

1, Alexa's website ranking is according to each specific website's browse rate ranking. The greater the browsing rate, the higher the ranking.

2, the browsing rate is defined on the domain site for statistics. For example: www.baidu.com, zhidao.baidu.com and baike.baidu.com will be counted as the same Web site because they belong to the baidu.com domain. However, there are exceptions, such as personal homepage, if the system can automatically distinguish from the URL address, will be considered as separate sites.

3. Sites that provide the same content will be counted as the same site. For example, Baidu uses www.baidu.com and baidu.com two domain names to publish the same content, then will be counted as the same website.

4. The amount of traffic included in statistics comes only from users using the Alexa toolbar (Alexa Toolbar). That is, only users download the Alexa toolbar and embed it in their browser. In this way, the user accesses a Web site, and the records they visit can count as the number of visits to the site. According to Alexa statistics, the user now uses the toolbar up to millions of.

5, the Alexa toolbar is currently used in Internet Explorer browser and Firefox browser is valid, access to other browsers will not be counted.

6, encounter a security or encryption site, Alexa toolbar will automatically shut down, so those high safety factors of the site, Alexa will not be able to search and statistics rankings.

Two) Alexa Browse Rate algorithm (Users reach + Page views)

1, a specific Web site is ranked, based on the browse rate of data according to the site's 3-month traffic records accumulated. That is, Alexa every three months to publish a ranking results, that is usually said ranking. Its calculations depend primarily on the number of access users (users reach) and page views. The Alexa system daily counts the number of visitors and page views per website, and obtains the current ranking by the geometric average of the cumulative value of these two three months.

2, Access users (users reach), refers to the number of people accessing a particular Web site over the Internet. Represents the proportion of people who access a particular Web site to the number of Internet users. That is: access to the number of users = (number of visitors/all Alexa users) * 100%,alexa per million people as counting units. Take the Webroot Web site Directory (www.webroot.org.cn), for example, if it has access to 2% users, that is, 1 million of internet users are randomly selected, 20,000 of whom visit the Webroot Web site directory.

3. Page views, which refers to the number of pages that a user accesses a particular Web site. Is the sum of the number of pages browsed by all users accessing the site. The average number of pages viewed by each user is averaged over the number of independent pages viewed by each user who accesses the site each day. The same person, same day, multiple browsing of the same page is recorded only once.

Three) The analysis of Alexa ranking mechanism

Although Alexa provides a lot of valuable information on its website, its real popularity is the ranking of global websites that have been quoted and repeatedly hyped by the media and that have caused a lot of controversy. According to the Alexa website of the "official statement", Alexa published the total ranking of the global site is through the collection of all Alexa toolbar return information, calculated by the comprehensive rankings. From this "official statement", we can see that the impact of Alexa ranking factor is two, one is the Alexa collection of information, the second is the Alexa of these information processing of the calculation method.

On the Alexa website, people can search for a specific Web site to query the number of visitors to their sites, Alexa provides a call to reach the technologists users (per million user visits, for short reach) data to indicate the number of visitors, This data refers to the average number of daily visits to a Web site per 1 million Alexa toolbar users. For example, November 3, 2004, the reach value of google.com is 178,500, that is to say, this day, every 1 million Alexa toolbar users of nearly 180,000 people visited the google.com.

Only the number of visitors, is not enough to reflect the situation of a Web site by netizens, Alexa also provides another data to reflect the use of a specific site to visit users, this is pageviews per user (the number of users browsing the page, referred to as PV). The PV value of a website is the average of the total number of pages viewed on the site by the Alexa toolbar users who visit the site on a daily basis, while the same person's repeated browsing of the same page is counted only once a day. Also take the November 3, 2004 google.com Access data for example, this day, google.com PV value is 4.0, that is to say, visitors to the average on the Google.com Web site to browse 4 pages.

With reach and PV these two data, Alexa can give the global website according to the comprehensive flow ranking, it put the site of this ranking is called Traffic Rank (traffic ranking, referred to rank), according to Alexa on its website explanation, This rank is determined by the geometric mean of reach and PV, which is the square root of the product. Obviously, the higher the reach and PV value of a website, the higher rank. Still take google.com as an example, its 4.0 PV value in the general site is not high, but, because Google search engine users are very many, its reach value is far higher than the general site, so that google.com rank to 3, that is, google.com the day of the global ranking is the third place. The world's highest ranked site is Yahoo.com, whose reach and PV values are relatively high on global sites.

Every moment, the world installed the Alexa Toolbar computer terminals will report to the Alexa terminal on the Internet access. According to this information, Alexa daily rankings of the global site do recalculation, that is to say, Alexa ranking is updated daily. Because almost all of the world's web sites in the Alexa monitoring range, and the daily update of the list is too intuitive, coupled with the public at any time available to check the data, so that the Alexa rankings on many occasions appear very sensitive.

(v) Other factors affecting Alexa rankings

1, the use rate of Alexa toolbar in different parts of the world, by the user's language, geography, culture and other aspects of the impact. Therefore, the English web site, compared to other languages of the site, the traffic data is more easily to be fully counted.

2, vulnerable to the site to their own publicity, the number of advertising, and other sites for its impact on the number of links.

3, different types of Web sites are sometimes not comparable, so can not blindly compare comprehensive rankings. such as professional web sites in the same category of sites are very much in the front, but compared with the Portal class site, the browsing rate may vary greatly.

4, the ranking of the site is best to actively add their own URL address to the Alexa, otherwise the statistics of traffic will be affected, and Alexa does not provide the detailed statistics of the number of visits to these sites.

5, the browsing rate is too small site statistics may be inaccurate, the overall ranking on the front (the greater the browsing rate) of the site statistics more reliable. Generally speaking, the monthly visit volume below 1000 or ranked 100,000 after the website statistics is inaccurate.